#pragma GCC optimize("Ofast") #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; #define rep(i,n) for(int i=0;i<(n);++i) #define reps(i,f,n) for(int i=f;i<=(n);++i) #define all(x) (x).begin(),(x).end() #define Fixed fixed << setprecision(14) #define int long long using pii = pair; constexpr int INF = 0x3f3f3f3f; constexpr long long LINF = 0x3f3f3f3f3f3f3f3fLL; constexpr int mod1 = 1e9+7; constexpr int mod2 = 998244353; constexpr int dy[] = {0,1,0,-1,1,-1,-1,1}; constexpr int dx[] = {1,0,-1,0,1,1,-1,-1}; template inline bool chmax(A &a, const B &b) { return b > a && (a = b, true); } template inline bool chmin(A &a, const B &b) { return b < a && (a = b, true); } template inline A updiv(const A a,const B b){ return (a + b - 1) / b; } template inline A gcd(const A a,const B b){ return b ? gcd(b,a % b) : a; } template inline A lcm(const A a,const B b){ return a / gcd(a,b) * b; } template using min_heap = priority_queue,greater >; template using max_heap = priority_queue; template using umap = unordered_map; signed main(void){ cin.tie(nullptr); ios_base::sync_with_stdio(false); int l, r, m, k; cin >> l >> r >> m >> k; if(k == 0){ return cout << "Yes\n", 0; } int a = updiv(m, k); int b = m / k; if(r / a - max(l-1, 0ll) / a && r / b - max(l-1, 0ll) / b){ cout << "Yes\n"; }else{ cout << "No\n"; } return 0; }